Hugh cassidy



(No Model.)

H. OASSIDY.

EXPANSIBLE REAMER.

No. 376,427. Patented Jan. 17, 1888.

N4 FEI'ERSv Fholoiilhognphar. Washington, Dv Q NITED STATES PATENT Orricri.

noon OASSIDY, or BROOKLYN, NEW YORK.

EXPANSIBLE REAMER.

$PECIFICATION forming pan: of Letters Patent No. 376,427, dated January 17, 1888.

Appication filed SeptembGrQG, 1587.. Serial No. 250,73R. (No model.) 7

To aZZ whom it may concern:

Be it known that I, HUGH CASSIDY, of the ers to a certain extent by making them conical in form; but it is not always allowable to make the hole conical. It has been also done by making the cutting edges on movable bits,

which are capable of adjustment on radial lines, so that they can be placed at greater or less distances from the axis.

So far as I am aware, all adjustable bits or expansible rcamers heretofore have had their movable bits supported on an adjustable cone, the forward or backward movement whereof caused the said bits to be thrust outward, or permitted them to retreat toward the center, as the case may be. This mode of construction gives solid bearings for the several bits,

. but does not admit of easy adj ustmcnt with accuracy.

My invention consistsin mounting the movable bits and controlling them by a scroll-plate acting in a plane transverse to the axis of rotation, so that all the bits will be simultaneously moved in one direction or the other, as the case may be.

It also consists in the particular structure of the several parts to effect the movement and locking in position of said bits.

In the following description reference is had to the accompanying drawings, wherein- Figure 1 is a perspective view of my reamer. Fig. 2 is a longitudinal section of the same. Fig. 3 is a transverse section on line 00 x.

The shaft or'bearer A is formed with a cylindrical head, d, and a shoulder, b. A plate, B, is fitted to turn freely on the cylindrical head (2 against the shoulder 12, and said plate is provided on itsface side with a scroll rib or thread, e, and with spanner-holesf,or other means whereby power may be applied to revolve said platcB when required. The cylind rical part d need not extend beyond the thickness of the plate B, as that is the member which is required to revolve. In front of said plate there is a head, D, which carries the radially-adjustable cutters E, and said head is most conveniently mounted on the extended end of the bearer and capable of longitudinal movement thereon, but is necessarily restrained from rotary motion thereon. This may be accomplished by making the forward extension of the bearer angular in cross-section and fitting saidhead D thereto; but it is more convenient to make said extension cylindrical and prevent rotation of the head D by ordinary meanssuch as a spline, g-as shown in Fig. 3. By these means the cutters E are compelled to rotate with the bearer A.

Each cutting-bit is fitted to move in a socket or groove cut radially in the head D, and one edge of each cutter is provided with sections of a spiral or scroll rib or thread having the same pitch as the scroll e on the plate B, and therefore adapted to mesh therewith. When the several cutters are thus in mesh with the scroll e, it is evident they will all be simultaneously moved outward 0r inward, as the case may be, by rotation of the plate B. The exposed edges h of the cutters E are properly ground to present salient edges.

It is convenient to cut the sockets for the cutting-bits entirely through from side to side of the head D, as shown, so that the cuttingedge It and the scroll-rib edge are both entirely exposed. It is then possible to look all the movable parts by forcing them back against the shoulder b by pressure applied to the front of the head D, and such pressure is easily applied by means of a screw-nut, F, applied on the extremity of the bearer and forcing back against the front of the head D; but said nut must necessarily be relaxed before the plate B can be revolved to change the adjustment of the cutters, and if said nut be moved too far the head D may move away from the scroll and slip the cutters out of engagement. To guard against this the nut F is recessed at the back, and a stop-nut, G, is placed therein, which will serve to keep the head D and its cutters from longitudinal movement far enough to go out of engagement with the scroll-rib e.

The bit-sockets being open toward three sides, it is convenient to apply a guide'rib, i, on the side of the bit in the direction of its movement and provide a correspondinggroove inside the socket, so that said cutter can only move in one direction in its socket.

Having described my invention, I claim- 1. In an expansible LQZIlIlQl, the bearer A, having a shoulder, I), a plate, 13, fitted to turn freely thereon against said shoulder, as setf orth, said plate being provided with a scroll rib or thread, 0, and cutting-bits E in engagement with said scroll-rib, and means whereby said bits are attached to said bearer to be revolved with it and free to move radially for adj ustment by the rotation of said scroll-plate.

2. In an expansiblc rearncr, a bearer, A,having an extension, (Z, and a shoulder, b, a plate, B, fitted to turn freely against said shoulder and provided with a scroll rib or thread, e, a head, D, fitted to and caused to revolve with said bearer A, provided with radial sockets, and cuttingbits Editted therein and adapted to engage said scroll-rib e, and means for looking all of said movable parts rigidly to said bearer when the properadjustmenthas been attained.

3. In an expansible reamer, the bearer A, having the shoulder I) and extension (I, the serollfaced plate 13, adapted to turn freely against said shoulder, the non-rotating head D, provided with radial sockets, the cntting'bits E, fitted to move therein and engage the scrollrib e, the recessed clamping-nut F, and the stop-nut G, substantially as set forth.

HUGH OASSIDY. \Vilnesses:

CHAS. Cnaxs'rox,

Enwn. C. EDWARDS. 

